title: Improving coherent contrast of petawatt laser pulses.
abstract: We report on an experimental study of the "coherent" contrast feature that frequently appears in petawatt(PW)-class laser pulses as an exponentially-rising pedestal within a few tens of picoseconds of the compressed pulse. We show that scattering from the diffraction gratings in the stretcher is the principal source of this feature. Replacing the gratings by new, higher-quality components resulted in an order-of-magnitude reduction in the intensity of the pedestal.
authors.affiliation: Central Laser Facility, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX, UK.
authors.forename: Chris
authors.initials: C
authors.lastname: Hooker
authors.forename: Yunxin
authors.initials: Y
authors.lastname: Tang
authors.forename: Oleg
authors.initials: O
authors.lastname: Chekhlov
authors.forename: John
authors.initials: J
authors.lastname: Collier
authors.forename: Edwin
authors.initials: E
authors.lastname: Divall
authors.forename: Klaus
authors.initials: K
authors.lastname: Ertel
authors.forename: Steve
authors.initials: S
authors.lastname: Hawkes
authors.forename: Bryn
authors.initials: B
authors.lastname: Parry
authors.forename: P P
authors.initials: PP
authors.lastname: Rajeev
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D007834:Lasers; D012031:Refractometry / Q000295:instrumentation*; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*